Container for treating metal articles by heat



May 9, 1933. J. c. HENDERSON CONTAINER FOR TREATING METAL ARTICLES BYHEAT Filed Sept. 23, 1930 2 Sheets-Sheet l ATTORNEYS May 9, 1933. J. c.HENDERSON CONTAINER FOR TREATING METAL ARTICLES BY HEAT Filed Sept. 25,1930 2 Sheets-Sheet 2 lNV ENTOR Jblm iflmo'arz,

BY J 6; WM

ATTORNEYS Patented May 9, 1933 "JOHN C HENDERSON, OF- ELIZABETH; NEWJERSEY, ASSIGZN0ITO"DBIV1E$HABMS COMPANY,- OF HARRISON, NEW- JERsEY, ,A.coRroRAmtoN'oR JERsEm CONTAINER"FOR TREATING METAIJ ARTICLESBY HEATApplication filed September 23, 1930. Seri'aIWo; 488,915.

My" invention relates to containers for treating metal: articles byheat, "and: has:

special reference to carburizing: containers.

@arburizin'gr containers or boxes are com fi monly'madeof heat-resistlngalloys, such as:

tomwalls ieither icastiin I a single piece or else These carbur zmg' Imade of rolled sheets.

boxes are sometimes as much as-fortyinches in'l'ength' by. eighteeninches in width, and consequently in case ofsingle plece cast boxes-alargemold must be made which re quires large: molding: and flask'equipment; Moreover, with-such cast boxes in order for the metalsto-fiow into themolds properly and-to-insure adequate strength, it isnecessary to make I the walls of substantiali thickness-,- the requiredthickness 1 varying with the cubical content of the *box:- The heatresisting" alloy is: expensive and; therefore,

any increase -in thickness adds to the expense of'ma'rmfacturatheboxes-are heavy and 255 bulliy to handle;- and the thick: walls ab:sorh" more'= heat than necessary when: the boxes are-in useStill-another disadvantage ofsuch cast boxes is that it: is difiicult tocast-the walls =of uniform thickness-through outyandanythin place in thewalls would be likely" tocause objectionable expansion andicontrantionstrains to be set up in the boxes.- Moreover blow-holesare likely: to

occur in the-casting which are notvisible While carburizi-ng boxes madeof cold rolled" sheet metalrequirea less amount of material and areappreciably less expens ve thanxa-boxnnade -of' a sin le casting, they40 also have numerous disa "antages- Gold rolled sheet metal isshapedandrolled froin ingots and, therefore, the metal must be'of' lowfcarbon content inorder that it may be sufficiently malleable to rolleasily. Owing- 'to such low carbon content, however, suchsheet metalhoxesha've aten'dencyto creep and grow whenmade ofheat-resistingialloy;which causes Warping and distortion' ofithe' WallsOf the hex,.and1.frequent1y= breaking of the welds: I The inetal'sheetsarehable ibe: scaly; split or'otherwise defectiveal thoughthe defectsiinay notibevisible: when the' bo'xi is' fabricated hut materially affect thehate-011 the box The several: sidew'a'lls of the box are usuallyfor-medxofm single piece of sheet metal, and the bending-.1 operationIQqIIlIEECl lS expensive;

The principal object of thepres'ent in vention is to overcome thedisadvantages above described of th'e' carburi'zi'ngihoxes as heretoforeconstructed," while retaining all'='- of: their advantages:

In-thedrawings:-

Figure 1 is a View in perspeot'ivaof a can c buriZing'bo-x embodying the'featu-res of my' invention in-their: preferred form; 1 I

Fig. 4; 5 and (i al c views in erspective* of the- 'bottomi-wall and twoof the si'd wal-ls of-the-box;

Fig. is a view' inperspective of? a side-- wall 01E the box made-up of za pl'Iurality of cast pieces secured'togetl'i'er";

Fig. 8 is a sectional vi'ewtaken; were line 8"8 'ofFig; 7 l a Fig. 91s aView inpersp ectivegof atcomponent part of the side wall? shown in'F'igh7-;

i Fig, 10 is aVieW-i'nperspective of'fa'cylins drical-box; and p i itFig-.i 11 is-a; sectional view takenon the-:- line 111-1 0f- Eig.10. a

The carburizing; boxillustrated in? Figsii 9m:

1 to; 6 of" the drawings 'isr pnovi dejd xwitha' bottom wall 2, opposedside wallsi i -andi opsposed sidewalls The several walls afre each madeotsa single "sheetica'st of the alloy referred: to in i m'y said 1patent? Asi the bottomwall is provided with: an up standing marginalrih"8; The vertical edges of the side walls-4 are=- provided with inwardly prejecting ribs 1O; and th eso-side walls and the side wallet"are: rovidedw mo side walls 6 abut against the inner sides of the sidewalls 4: and are positioned against the inner sides of the vertical ribs10.

When the parts are thus assembled, weld; ing material-indicated at 12 isappliedto the corner formed by the marginal rib 8 of the bottom wall andthe adjacent portion of the side walls, and to the corners formed by thevertical ribs 10 and adjacent portions of the side walls 6. The uppercorners of the box formed by the abutting ribs 10 are also securelyWelded.

With this construction it will be apparent that anextremely strong andrigid box is provided. The ribs 8 and 10 not only reinforce the cornersof the box but also provide shoulders for effectively receiving thewelding material so that there is no danger of the welds being burnedout and broken while the box is in use. The upper marginal rib or band11 effectively reinforces said edge so as to prevent breaking down byheat., 1

In casting the walls, the patterns may consist merely of a piece ofsheet metal having strips secured thereon to form the ribs on the sidewalls when cast. It has been found that with the heat-resisting alloyem- "ployed, the castings may be of a thickness of but three-sixteenthsof an inch and that awall of one-eighth of an inch in thickness ivesthe'necessary strength in most cases.

y making the walls of the box of thin sheet castings there is not thedanger of blowholes as in the case of a single piece cast box, for thereason that the chilled surfaces of these thin castings meet each otherand there is no intermediate area in which 'defects may occur.

condition to the user, who may easily as-' semble the parts and Weld theseams, so that there is a substantial saving in transportation costs.Also, in case one wall of the box becomes burned out or otherwiseinjured, it may be easily replaced upon melting the welds.

- In case it is desired to manufacture a box of such length that thewalls thereof cannot be easily cast in a single piece, the walls maybemade up of several pieces 14 (Figs. 7, 8 and 9) having their edgeswelded together. The welding seam is preferably formed by anoffsetportion 16 on one edge of onefpiece'providing shoulders 17 and 18.

The shoulder 17 abuts against the edge of the adjacent piece, and theshoulder 18 forms a corner with the adjacent portion'of the adjacentpiece for the reception of welding material.

In making a cylindrical box the bottom wall may consist of a circularcast sheet 18 having an upstanding longitudinal flange 20, and the sidewall may consist of a plurality of pieces 22 having overlapping seams 24which are welded, the Welding seams being preferably of the constructionof the seams shown in Figs. 7, 8 and 9.

In some cases where it is desired to make the box other than withstraight sides, in stead of casting the walls in curved form they may bebent, it being found that. the thin castings of the alloy are capable ofbending to a certain extent. Also, if desired the walls may be cast withreinforcing corrugations. .Furthermore, the walls may be of varyingthicknesses to secure reenforcement as desired, such as by greaterthickness at the center, which of course is not possible with rolledsheets.

Carburizing boxes are usually used in inverted position, but in caseswhere they are used in upright position a flanged cover may be provided.It will be apparent that the flanged cover may be constructed in amanner similar to the body of the box.

As will be evident to those skilled in the of the other sheet, andwelding material applied to the corners formed by the upper edge of saidrib on the bottom wall and adjacent portions of said side walls, and bythe outer edges of the ribs on said side walls and the adjacent portionsof the adjacent side walls so as to Weld the side walls together and tothe bottom wall, each of the side walls having an outwardly projectingmarginal rib at its upper edge so as to form a reinforcing band for theupper edge of the container.

2. A metallic receptacle for usein heat-- treating furnaces comprisingspaced plates having flanges directed towards each other, plates havingthe ends thereof overlapping said flanges, and a flanged bottom memberreceiving the lower portions of said plates, said parts being joinedtogether- 3. A metallic receptacle for use .in heat treating furnacescomprising side plates, channel end plates, and a cupped bottom ofprecast metal, and said parts being joined together by Welding.

4. A metallic receptacle for use in heat treating furnaces comprisingside plates, channel ends and cupped bottom, all of precast metal andjoined together by Welding, said cupped bottom forming a bumper andreinforcement.

In testimony whereof, I have signed my name to this specification.

JOHN C. HENDERSON.

